View of /netsukuku/src/conf.c

    1 /* This file is part of Netsukuku
    2  * (c) Copyright 2005 Andrea Lo Pumo aka AlpT <alpt@freaknet.org>
    3  *
    4  * This source code is free software; you can redistribute it and/or
    5  * modify it under the terms of the GNU General Public License as published
    6  * by the Free Software Foundation; either version 2 of the License,
    7  * or (at your option) any later version.
    8  *
    9  * This source code is distributed in the hope that it will be useful,
   10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
   12  * Please refer to the GNU Public License for more details.
   13  *
   14  * You should have received a copy of the GNU Public License along with
   15  * this source code; if not, write to:
   16  * Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
   17  *
   18  * --
   19  * conf.c
   20  *
   21  * General configuration file loader and parser. To understand how to use it,
   22  * see {-conf-usage-}.
   23  */
   24 
   25 #include "includes.h"
   26 #include <ctype.h>
   27 
   28 #include "conf.h"
   29 #include "common.h"
   30 
   31 /*
   32  * parse_config_line
   33  *
   34  * it reads the `line' string and sees if it has a valid option assignment
   35  * that is in the form of "option = value".
   36  * On success it stores the option name with its value in the environment.
   37  * On failure fatal() is called, so it will never return ;)
   38  * `file' and `pos' are used by fatal() to tell where the corrupted `line' was.
   39  *
   40  * `opt_head' is the head of the llist which keeps all the valid options.
   41  */
   42 void parse_config_line(char *file, int pos, char *line, ntkopt *opt_head)
   43 {
   44   ntkopt *opt=opt_head;
   45   size_t optlen;
   46   int e=0;
   47   char *value;
   48 
   49   while(isspace(*line))
   50     if(!*(++line))
   51       /* It's just an empty line */
   52       return;
   53 
   54   /* Check if `line' contains a valid option */
   55   list_for(opt) {
   56     optlen=strlen(opt->opt);
   57     if(!memcmp(line, opt->opt, optlen)) {
   58       e=1;
   59       break;
   60     }
   61   }
   62   if(!e)
   63       fatal("The line %s:%d does not contain a valid option. Aborting.",
   64         file, pos);
   65 
   66   /* Eat the remaining spaces */
   67   value=line+optlen+1;
   68   while(isspace(*value))
   69     value++;
   70 
   71   if(!*value) {
   72     /*
   73      * Consider this option as boolean and set it to "1"
   74      */
   75     opt_add_value(opt->opt, "1", opt);
   76     return;
   77   } else if(*value == '=')
   78     value++;
   79 
   80   while(isspace(*value))
   81     value++;
   82   if(!*value) {
   83     /*
   84      * We are in this case:
   85      *  opt =
   86      * missing value after the '='
   87      */
   88     fatal("%s:%d: syntax error: no value has been assigned "
   89         "to the \"%s\" option",
   90         file, pos, opt->opt);
   91   }
   92 
   93   opt_add_value(opt->opt, value, opt);
   94 }
   95 
   96 /*
   97  * load_config_file
   98  *
   99  * loads from `file' all the options that are written in it and stores them
  100  * in the environment. See parse_config_line() above.
  101  * If `file' cannot be opened -1 is returned, but if it is read and
  102  * parse_config_line() detects a corrupted line, fatal() is directly called.
  103  *
  104  * `opt_head' is the head of the llist which keeps all the valid options.
  105  *
  106  * On success 0 is returned.
  107  */
  108 int load_config_file(char *file, ntkopt *opt_head)
  109 {
  110   FILE *fd;
  111   char buf[PATH_MAX+1], *p, *str;
  112   size_t slen;
  113   int e=0;
  114 
  115   if(!(fd=fopen(file, "r"))) {
  116     fatal("Cannot load the configuration file from %s: %s",
  117       file, strerror(errno));
  118     return -1;
  119   }
  120 
  121   while(!feof(fd)) {
  122     setzero(buf, PATH_MAX+1);
  123     fgets(buf, PATH_MAX, fd);
  124     e++;
  125 
  126     if(feof(fd))
  127       break;
  128 
  129     str=buf;
  130     while(isspace(*str))
  131       str++;
  132     if(*str=='#' || !*str) {
  133       /* Strip off any comment or null lines */
  134       continue;
  135     } else {
  136       /* Remove the last part of the string where a side
  137        * comment starts,  #a comment like this.
  138        */
  139       if((p=strrchr(str, '#')))
  140         *p='\0';
  141 
  142       /* Don't include the newline and spaces at the end of
  143        * the string */
  144       slen=strlen(str);
  145       for(p=&str[slen-1]; isspace(*p); p--)
  146         *p='\0';
  147 
  148 
  149       parse_config_line(file, e, str, opt_head);
  150     }
  151   }
  152 
  153   fclose(fd);
  154 
  155   return 0;
  156 }